Domain not active but how can I delete it and use it on another host? HELP!

I want to delete my domain...it isn't active and I waited for it to expire. Got the phone calls from wordpress, everything. I want to use it at WIX and I couldn't transfer it so waited for it to expire and it is expired but still showing up under my domains. How can I permanently delete it so I can see that's available from another host? HELP! Need to do this ASAP